Lt. Gen. Susan Helms will not be the vice commander of Space Command after a prominent Democratic lawmaker successfully blocked her nomination for overturning a sexual assault conviction. (Air Force)

Lt. Gen. Susan Helms will not be the vice commander of Space Command after a prominent Democratic lawmaker successfully blocked her nomination for overturning a sexual assault conviction.

Helms has applied for retirement, Air Force spokesman Lt. Col. Allen Herritage said on Nov. 8.

Sen. Claire McCaskill, D-Mo., has blocked Helms’ nomination since April because Helms overturned the sexual assault conviction of Capt. Matthew Herrera at Vandenberg Air Force Base, Calif., in February 2012. Herrera was punished administratively and kicked out of the Air Force in December.

Helms decided not to approve the conviction because she could not be satisfied “beyond-a-reasonable-doubt” that the prosecution met the burden of proof, Space Command spokeswoman Lt. Col. Kathleen Cook told Air Force Times in March.

McCaskill has said Helms’ decision made it more difficult for victims of sexual assault to seek justice. She was also outraged earlier this year when a three-star general overturned the sexual assault conviction of Lt. Col. James Wilkerson, the former inspector general for Aviano Air Base, Italy.

“In both instances, you had the victim testifying to one set of facts, and the accused testifying to another,” McCaskill said at a May 7 Senate Armed Services Committee hearing. “In both instances, juries selected by those generals said they believed the victim. And in both of those instances, the general said, ‘No, no, we believe the member of the military.’”